Abstract: The invention is a complete method for producing consistent medical image data that is verifiably correct, comprising taking a series of photos of the same wound, each photo being taken with a calibration slate which appears in the photo; and calibrating the photos for color using the calibration slate, the calibration slate including a means of quantifying focus by means of a focus chart with a grading system included on the slate, the slate having a front side and a back side, and an adhesive attached to the back side of the calibration slate, to facilitate attaching the calibration slate to a subject.